Fake news was one of the biggest themes of 2016, and US president-elect Donald Trump and his supporters on the alternative right were not the only culprits. Another important manufacturer of fake news was the British government, especially when it came to ministerial statements on war-torn Yemen.

I hesitate to use the term "lie," but we have learned through experience that British ministers cannot be trusted to tell the truth when they make statements about Yemen.

One manifestation of this pernicious culture of falsehood concerned Philip Dunne, then UK defence minister, who told the British parliament in May that "we assess that no UK-supplied cluster weapons have been used and no UK-supplied aircraft have been involved in the use of cluster weapons in the current conflict in Yemen."

More recently the present UK defence secretary Michael Fallon was obliged to tell MPs that British-made cluster bombs had indeed been dropped on Yemen by Saudi Arabia.

Dunne's misleading assertion about cluster bombs was part of a long series of inaccurate written and oral statements to parliament made by British ministers.

The culprits included former UK foreign minister Philip Hammond before he was moved to the finance ministry in the wake of the UK’s exit vote from the European Union. Hammond said in February that Britain had "assessed" that there had not been any breach of international humanitarian law in Yemen by the Saudi-led coalition.

However, when Boris Johnson became UK foreign secretary in July, he immediately ordered his predecessor's untrue statement to be corrected. In a humbling moment for Hammond, the UK foreign office put out a statement which made it clear that his remark had been false. No assessment of any kind had been carried out.

There is, therefore, no question that Hammond (and others including the current UK Middle East minister Tobias Ellwood) systematically misled the British House of Commons on Yemen. The effect of their statements was to protect Saudi Arabia as it led a series of bombing raids which have wiped out weddings, attacked hospitals, funerals, markets and homes, in the process killing thousands of people.

It is important to remember that misleading the House of Commons is one of the most serious offences which any minister can commit in Britain, and all the more so when it concerns a matter of life and death. The UK’s ministerial code of conduct is completely unambiguous on this point. It commits ministers to giving "accurate and truthful information to parliament."

Any government minister who misleads the House of Commons is under a duty to return to the House and correct any false statement at the first opportunity. And if ministers deliberately mislead the House, they must resign because they can no longer be trusted to occupy their office.

The false statements put out by ministers to the UK parliament about the British assessment of the carnage being carried out by the Saudi-led coalition bombers on Yemen were therefore a deadly serious matter. That is why I am very puzzled why the British government has not treated the matter seriously. Shockingly, there has been no apology. The corrections made in July were quietly shuffled out on the final day before the parliament’s summer recess.

Crucially, there appears to have been no investigation into how ministers repeatedly came to mislead the UK House of Commons and no rebuke for those responsible. This is truly shocking. For any government department with high standards of integrity, it should have been a matter of urgent importance to understand how MPs and the nation were misled and what went wrong.

In the autumn, I rang the UK foreign office’s press office to ask whether there had been an inquiry into the statements and whether any disciplinary action had been taken against those responsible. A press officer said that the matter was already the subject of a freedom of information request. She asked me to wait until this request had been answered, stating that I would then be able to discover the truth about what had happened. I agreed to her request, but now regret doing so.

The answer to the freedom of information request, which finally arrived towards the end of December after a lapse of more than two months, contains no reference of any kind to an inquiry into how UK ministers came to mislead parliament, nor is there any reference to subsequent disciplinary action.

I got back in touch with the press spokesperson, saying that I felt that she had led me up the garden path. I then put the questions to her again: had there been an investigation into how ministers had misled parliament, and had anyone been disciplined as a result? I have received no answer to either question.

I can only reach one conclusion from my dealings with the UK foreign office over this very serious matter: there has been no inquiry as to how British MPs came to be misled, and there have been no consequences of any kind for those responsible.

The failure to launch an inquiry would be extremely troubling in any circumstances. It is nothing short of repugnant when it involves Yemen, a country on the verge of famine and where thousands have been killed by bombers from the Saudi-led coalition. I saw for myself the horror ordinary Yemenis are experiencing when I visited the country last July. Hospitals cannot access left-saving medicines. Millions are on the edge of starvation. Millions more have fled their homes. And innocent people are being killed by air strikes.

The most generous construction to be put on the failure to hold an inquiry is that there is an insouciant and careless culture in the Middle East section of the UK foreign office. Ministers may feel that they can utter untruths regardless of the consequences. Their statements may be seen as purely weightless and part of a “post-truth” environment where government statements have no connection with any underlying reality.

There is, however, a sinister alternative explanation: the British ministers were deliberately lying in order to cover up the truth about what they knew about the carnage being inflicted on the people of Yemen by the Saudi-led coalition. There was no inquiry, and no punishment, because nobody, in their view, had done anything wrong.

If that is so, Hammond's statement to British MPs last February was not a mistake. It was part of a deliberate attempt to deceive them in order to cover up mass murder carried out by British allies in one of the ugliest conflicts in the world. If that is so, Hammond and his ministerial colleagues have blood on their hands. He deceived the UK House of Commons over a matter of life and death.

Once again, I urge the UK foreign office to answer the questions I have been putting to it since the autumn. Has there been an inquiry into how Hammond and fellow ministers came to mislead the UK parliament over the British "assessment" of Saudi breaches of international humanitarian law?

If such an inquiry did take place, was anyone disciplined? It is essential that ministers come up with answers to these questions. Otherwise British ministers will never again be trusted when they speak out on the subject of this terrible